A BART police officer was accidentally shot and killed by a fellow officer while performing a probation search in Dublin Tuesday afternoon, police said.

The brother of fallen BART Police Sgt. Thomas A. Smith said the 42-year-old was a “great father, great uncle, great officer.” Smith leaves behind his wife, who also works in the BART Police Department, and his 6-year-old daughter, according to the Officer Down Memorial Page, a website dedicated to fallen officers. The shooting marks the first time a BART police officer has been killed in the line of duty.

Transit agency officials said in a statement that the shooting occurred at Park Sierra Apartments, near the intersection of Dougherty Road and Park Sierra, around 2 p.m., and Smith, a 20-year veteran of the department, was transported to Eden Medical Center in Castro Valley, where he died of his injuries.

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A number of BART officers had come to the apartment complex to do a probation search, according to Sgt. J.D. Nelson of the Alameda County Sheriff's Office. They were looking for a man suspected of robberies aboard BART trains. Officers went into the apartment and at some point one officer accidentally discharged his gun, wounding Smith fatally.

“They made entry in the apartment and during the search one officer fired a shot, striking another in the apartment,” Nelson said.

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The person on probation who lives at the apartment, suspected of robbing BART passengers, was not at home, and BART officers knew that, but they were not sure if anyone else was inside the apartment, which is why, wearing bullet proof vests, they kicked in the door and entered with guns drawn for the probation search.

The city of Dublin contracts with the sheriff's office for police services.

“When you're on probation, you are let out of jail with an agreement that your home or car or anything can be searched at any time,” Nelson said.

Sgt. Smith

Nelson said he assumes that the officers had their guns drawn as they entered the apartment but that the details of how or why the officer's gun went off remain unclear. It is believed the bullet found its way past Smith’s vest near his armpit as he carried his weapon in front of him.

Dublin police, the Alameda County Sheriff's Department and the FBI are among the agencies investigating the shooting.

The officer who did the shooting, a 10-year veteran, and all other BART officers at the shooting scene were taken to the Dublin Police Department for questioning.

In an emailed statement, BART officials said, "The entire BART organization is deeply saddened by this tragic event and we ask the public to keep the officer’s family in its thoughts and prayers.”

BART Police Chief Kenton Rainey said Tuesday evening his department is in mourning and would share more information Wednesday.

As word spread of the shooting, a large crowd gathered at Eden Medical Center, giving Smith an emotional send off. When a flag-draped coffin emerged, the crowd of officers saluted as Sgt. Smith's body was taken away.

“Our condolences goes out to the immediate family and friends, and the extended BART family, and the entire BART district,” Rainey said.

Attorney John Burris has been monitoring reforms made in the BART Police Department. He believes procedures will be the focus of the review.

“I know BART police officers go to academy. I would expect training to be proper,” Burris said. “That would mean there was a breakdown, and that's what the investigation will determine.”

The BART Police Department enacted serious reforms in the wake of the controversial shooting of Oscar Grant on a BART platform. Grant, who was unarmed, was shot and killed by former officer Johnannes Mehserle in the early morning hours of New Year's Day in 2009. Mehserle was later convicted of involuntary manslaughter.

Tuesday’s shooting marks the first time in more than a decade that an officer in Alameda County has been killed by friendly-fire. Back in 2001, two Oakland police officers shot Officer William Wilkins. He was working as an undercover detective at that time, and the two officers did not realize he was one of their own.

Charges were never filed against the two officers. Wilkins' widow sued the city of Oakland and received a $3 million settlement.

The Tommy Smith Memorial fund has been set up at Wells Fargo Bank. Deposits can be made at any Wells Fargo Bank, Account # 5148561086 under Kellie Smith. Or they can be mailed to: